Sen. Lindsey Graham (R-SC), accompanied by Sen. John McCain (R-AZ) and Sen. Ron Johnson (R-WI), speaks during a press conference about their resistance to the so-called "Skinny Repeal" of the Affordable Care Act on July 27. Photo: Reuters

A Republican senator seems to think the vote to repeal Obamacare was defeated in part by the John McCain tumor effect. Sen. Ron Johnson said on Tuesday perhaps McCain's health and recent brain tumor discovery adversely affected his vote on the Senate bill to repeal the current healthcare system.

On July 27, to a standing ovation from his colleagues, McCain returned to the Senate floor after surgery to remove a blood clot revealed a brain tumor. After a long day, at around 1:30 a.m., McCain joined Senate Democrats and voted no on the “skinny repeal" of the Affordable Care Act.

Johnson said on Tuesday McCain’s brain tumor and the late hour could have affected the Arizona senator’s judgment.

"We did get a call from Paul [Ryan] and he assured us that skinny repeal was not going to pass the House it would have to go to conference," said the Wisconsin senator on AM560 "Chicago's Morning Answer.”

"Again, I'm not gonna speak for John McCain — he has a brain tumor right now — that vote occurred at 1:30 in the morning, some of that might have factored in," he continued.

A radio host is heard asking “Really?” in a seemingly shocked tone.

"Again, I-I-I don't know exactly what we really thought and again I don't want speak for any senator," Johnson responded.

"I really thought John was going to vote yes to send that to conference at 10:30 at night. By about 1, 1:30, he voted no. So, you have talk to John in terms what was on his mind."

McCain spokeswoman Julie Tarallo released a statement: "It is bizarre and deeply unfortunate that Sen. Johnson would question the judgment of a colleague and friend. Sen. McCain has been very open and clear about the reasons for his vote."

McCain said at the time the defeated bill did not offer meaningful reform and that its defeat presents "an opportunity to start fresh" on legislation crafted by lawmakers in both parties.

"I encourage my colleagues on both sides of the aisle to trust each other, stop the political gamesmanship and put the healthcare needs of the American people first," McCain said.

Top congressional Democrats urged a bipartisan effort to fix problems in the Obamacare law without repealing it. "Change it, improve it, but don't just take a knife and try to destroy it and put nothing in its place," top Senate Democrat Chuck Schumer said.